<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title><style>
div{width: 600px;
    height: 600px;
background: red url(./cat.gif) no-repeat center;
}
.one{
    width: 427px;
    height: 240px;
    background: gold url(./cat.gif);

/* 复合属性要注意空格 重叠 */
}


    </style>
</head>
<body>
    <div>4</div>
    <div class="one">5</div>
    
</body>
</html>